Texas Instruments TI-58C

Datasheet legend
Ab/c: Fractions calculation
AC: Alternating current
BaseN: Number base calculations
Card: Magnetic card storage
Cmem: Continuous memory
Cond: Conditional execution
Const: Scientific constants
Cplx: Complex number arithmetic
DC: Direct current
Eqlib: Equation library
Exp: Exponential/logarithmic functions
Fin: Financial functions
Grph: Graphing capability
Hyp: Hyperbolic functions
Ind: Indirect addressing
Intg: Numerical integration
Jump: Unconditional jump (GOTO)
Lbl: Program labels
LCD: Liquid Crystal Display
LED: Light-Emitting Diode
Li-ion: Lithium-ion rechargeable battery
Lreg: Linear regression (2-variable statistics)
mA: Milliamperes of current
Mtrx: Matrix support
NiCd: Nickel-Cadmium rechargeable battery
NiMH: Nickel-metal-hydrite rechargeable battery
Prnt: Printer
RTC: Real-time clock
Sdev: Standard deviation (1-variable statistics)
Solv: Equation solver
Subr: Subroutine call capability
Symb: Symbolic computing
Tape: Magnetic tape storage
Trig: Trigonometric functions
Units: Unit conversions
VAC: Volts AC
VDC: Volts DC
Years of production: 1978-? Display type: Numeric display  
New price:   Display color: Red  
    Display technology: Light-emitting diode 
Size: 6½"×3"×1½" Display size: 10(8+2) digits
Weight: 12 oz    
    Entry method: Algebraic with precedence 
Batteries: 3×"AA" NiCd Advanced functions: Trig Exp Lreg Cmem 
External power: AC-9131 adapter (3.3VAC 500mA)   Memory functions: +/-/×/÷ 
I/O: Printer port     
    Programming model: Partially merged keystroke 
Precision: 13 digits Program functions: Jump Cond Subr Lbl Ind  
Memories: 60(0) numbers Program display: Keycode display  
Program memory: 480 program steps Program editing: Insert/delete capability  
Chipset:   Forensic result: 9.000004661314  

ti58c.jpg (27598 bytes)The TI-58C was a TI-58 programmable calculator with continuous memory. Not as flexible perhaps as magnetic card storage, continuous memory solved a major problem nevertheless: what do you do with a calculator with an enormous memory capacity, but with no way to retain programs or data once it is turned off? Entering a 480-step program, after all, may take more time than it takes for the rechargeable battery pack to drain.

The TI-58C became a very popular machine. It was definitely a high-end programmable calculator, with many powerful features, not the least of which was the removable solid state software module. In addition to a dozen or so modules produced by TI, other modules also became available for specialized applications. In some cases, even the calculator itself was heavily customized: keys were removed or creatively relabeled. This is well illustrated by a German product, a customized TI-58C used by agents of the Allianz insurance company.

The example program below computes the logarithm of the Gamma function for positive arguments using the Lanczos-approximationto a precision of 10 or more digits. Registers 1 through 6 must be preloaded with constants before the program can be used.

STO 01	 92.20704845211
STO 02	-83.17763708288
STO 03	 14.80283193078
STO 04	 -0.2208497079533
STO 05	  2.506628283501
STO 06	  3.85

000 76	LBL
001 11	A
002 42	STO
003 07	07
004 85	+
005 43	RCL
006 06	06
007 75	-
008 24	CE
009 23	ln
010 65	*
011 53	(
012 43	RCL
013 07	07
014 75	-
015 93	.
016 05	5
017 95	=
018 94	+/-
019 85	+
020 53	(
021 04	4
022 42	STO
023 00	00
024 43	RCL
025 05	05
026 85	+
027 73	RCL IND
028 00	00
029 55	/
030 53	(
031 43	RCL
032 07	07
033 85	+
034 43	RCL
035 00	00
036 75	-
037 01	1
038 54	)
039 97	DSZ
040 00	00
041 00	00
042 26	26
043 54	)
044 23	ln
045 95	=
046 92	RTN